Elevator control system



April 3, 1934.

F. E. LEWIS 1,953,115

ELEVATOR CONTROL SYSTEM Filed April 20, 1929 2 Sheets-Sheet l s oa INVENTOR Fran/f E L e Wis.

ATTORNEY Patented Apr. 3, 1934 ELEVATOR CONTROL SYSTEM Frank E. Lewis, Forest Hills, Pa., assignor to Westinghouse Electric & Manufacturing Company, a corporation of Pennsylvania Application April 20, 1929, Serial No. 356,732

24 Claims.

My invention relates to control systems and has particular relation to control systems for elevator hoists and similar machinery.

An object of my invention is to provide a control system for a plurality of ye Aides movable over a predetermined path, wherein the operation of each of the vehicles is automatic, requiring no attendants or operators to control the same.

Another object of my invention is to provide a control system for a bank of elevators in which the entire operation of the elevators is automatic, dispensing with the necessity for attendants to control the cars.

Another object of my invention is to provide a control system for a plurality of elevators in which the cars will be dispatched at regular intervals to make complete round trips and, when so dispatched, will automatically stop to take on and 39 let off passengers in the same manner as though attendants on each of the cars were controlling the same.

Another object of my invention is to provide a control system for a plurality of elevators which e5 shall include devices for permitting one of the cars to operate as an automatic push-button elevator, while the remainder of the cars are out of service, wherein two cars may be made to operate as interconnected push-button elevators to 39 give service while the remainder of the cars are out of operation and wherein all of the cars may be operated as a bank of elevators dispatched at regular intervals to automatically perform all of the functions of elevator service without the necessity of attendants on the cars.

Another object of my invention is to provide an elevator system for use in a. building having normal terminals and additional floors beyond the normal terminals wherein the car or cars will 49 normally operate between the normal terminals but may, when service at additional floors is desired, move to such floors to give service thereat only when actual service is desired.

Modern elevator service requires that, in a bank of elevator cars, the cars shall be so distributed throughout the shafts or hatchways that, at no time, will two or more cars pass the same floors at approximately the same time, and such service also requires that the cars shall stop for passengers only when service is desired and only when the car making the stop is travelling in the direction indicated by the person or persons desiring to use the car. It is also desirable that, in any bank of elevators, one or more of the cars may be taken out of service when trafiic condi tions warrant, leaving the remainder of the cars to answer the calls for service under such light trafiic conditions.

The prior elevator systems, utilizing an attendant on each of the cars, could readily be made to answer all of the requirements for such service, but such elevators require, as an essential part of the system, the personal supervision of at least one person on each of the cars. I propose to construct an elevator system in which all of the functions, which have previously been performed by elevators having attendants thereon, shall be performed with an elevator system of the automatic type requiring no attendants.

My invention will be described with reference to the accompanying drawings wherein.

Figs. 1 and 2 jointly constitute a diagrammatic view of an elevator system including two elevator cars operating between the first and fourth floors of a building and operable, under certain conditions hereinafter specified, to a basement floor below the first floor of such building.

Referring to the drawings, I have illustrated two elevator cars C and C, each operable in its hatchway (not shown) past a basement floor, 1st, 2nd, 3rd and 4th floors in a building, the floors being designated by dotted lines marked with the legend, Basement, 1st floor, 2nd floor, 3rd floor and 4th floor.

Each of the elevator cars, C and C, is suitably driven by means of a variable-voltage drive, that for car C including a driving motor M illustrated as of the shunt-wound type, having its field winding MF and its armature MA connected, in parallel relation, to a suitable source of current supply indicated by line conductors L1 and L2. The armature MA of the drive motor M is directly coupled to an armature GA of a generator G, which armature is, in turn, connected in loop circuit with the armature EMA of a hoisting motor EM.

The generator G is provided with a separatelyexcited field winding GF and a cumulative series field winding GSF so proportioned as to produce substantially constant speed regulation for the hoisting motor EM, independent of variation in load upon the car C.

The hoisting motor EM has its separately-excited field winding EMF connected, for constantvoltage energization, to the source of power represented by line conductors L1 and L2. The hoisting motor EM has its armature EMA directly coupled to a hoisting drum D over which passes a cable Ca for supporting the elevator car C.

The driving equipment for elevator car C is identical, in all respects, with that just described for car C, and, in the following description, primed reference characters, corresponding to the reference characters applied to the elements for car C, will be used to indicate the elements of the driving and control system for car C.

At each of the 1st, 2nd and 3rd floors, I have illustrated a passenger-operated push-button for each direction of travel, those for the 1st floor being indicated by the reference character P113 to be used for calling any of the cars to take a passenger down from the first floor, and FlU to be used to call any of the cars to take a passenger up from the first floor. Push-buttons FZD, FZU, F3D and F3U perform a similar service for the 2nd and 3rd floors, respectively. A push-button FB at the basement floor is used to register a call for service for that floor, while a button F4 performs a similar service at the 4th floor.

Buttons FB, FlD, etc., are connected, as hereinafter described, to control all of the cars in the bank to cause the cars to move to the corresponding floors to permit passengers to board the cars, while each of the cars is provided with a plurality of push-buttons mounted within the car, one button being provided for each floor served by the cars to be operated by passengers within the car to cause the same to be moved to the various floors at which passengers desire to leave the car. The buttons for car C are designated by the reference characters CB, C1, C2, C3 and C4, for the basement, 1st, 2nd, 3rd and 4th floors, respectively.

Each of the cars is provided with a floor selector FS suitably driven to duplicate, in miniature, the movements of the cars past the floors which they serve. Each of the floor selectors FS comprises a suitable base FSB, upon which are mounted a group of relatively short contact segments FCU connected, respectively, to each of the up-call buttons FlU, FZU, F3U and F4 mounted at the various floors. A second group of segments FCD are connected, respectively, to the down-call buttons FB, F11), FZD and F3D mounted at the various floors. A third group of segments CCU is provided having its segments connected, respectively, to each of the car-call buttons CB, C1, C2, etc., carried by the car, while a fourth group CCD is, in like manner, also connected to the car-call buttons.

Each of the iioor selectors is further provided with a plurality of normally-closed switches arranged in a group indicated by the reference character RU for the purpose of resetting or restoring the operated up floor-call buttons FlU, FZU, etc. When such call has been answered, while another group RD performs a similar service for the down-call buttons FB, FlD, etc.

Each of the floor selectors is provided with a movable arm A so arranged as to be moved across the floor selector base FSB in correspondence to the movements of the car C with which it is associated by means of a screw S suitably connected to some part of the driving equipment for elevator car C. The movable arm A comprises a lever extending to the right-hand side of the drawing, which carries a plurality of contact brushes l2 and 13 cooperating, respectively, with the groups of segments CCD and FCD as the car moves downwardly. The right-hand portion of the arm A also carries adevice for momentarily opening each of the switches in group RD, this device being indicated as a wedge-shaped piece of insulating material 14 so aligned with the switches in group RD as to enter between, and

separate the contact members of such switches. A similar operating device 15 is arranged to engage and operate a throw-over switch 16 of the type commonly used in automatic push-buttonelevator floor-selector systems.

Similar contact brushes l8 and 19 are mounted upon the left-hand side of the arm A to coop erate, respectively, with contact-segment groups CCU and FCU, while switch-operating devices 20 and 21 cooperate, respectively, with the group of normally-closed switches RU and with additional normaliy-closed switch 22 when the car is moving upwardly.

The selector arm A is suitably rocked about the screw S to cause the right hand brushes and switch-operating devices to engage the cooperating segments and. switches, when the car is moving downwardly, h 7 means of a throw-over magnet DS, or the arm A is rocked in the other direction, when the car is moving upwardly, by means of a throw-over magnet US. The selector described in the foregoing description is similar to the selectors now in general use for operating elevator signal systems and push-button control systems, e believe needs no further descrip tion.

The direction of movement of the elevator car C is suitably determined by the operation of up-direction switch 1 and. a down-direction switch 2 operable to reverse the c ent supplied to the generator field winding Gr, which, in turn, determines the direction of current supplied to the armature EMA of the hoisting motor EM.

The dir ction switches l and 2 are suitably controlled an up-direction-determining relay DD and a down-direction-determining relay DD.

In order that, when a car is started in either direction, it shall continue to travel in that di-- rection as each stop is made to take on or let off passengers, a through-trip relay 6 and a restart relay 7 are provided. The through-trip relay insures that the car will move to that terminal in the direction in which the car starts its initial movement, while restart relay '7 operates the car to restart after each stop is made to take on or let of]? passengers.

legend, Dispatche1", is utilized to time the departure of each of the cars from its lower and from its upper terminal. The dispatcher illustrated represented by a constant-speed motor DM driving a plurality of dispatching discs 23, 23, 24, and 24. to start the cars, as hereinafter J described. A switch DM is provided to connect the dispatching motor DM to the source of power.

Each of the cars is provided with a suitable collapsible gate, that, for car C, is repr sentcd by the reference character GS, while each of the hatchways in which the cars move, is provided with a suitable hatchway door for each of the floors served by that car. The doors associated with car C are indicated by the reference oharacters DB, D1, D2, D3 and D4 located at each direction of the of the basement, 1st, 2nd, 3rd and 4th floors, respectively.

Each of the cars is further provided with a load switch LS which opens one set of contact members and closes another set when load upon the reaches a predetermined value.

Since my elevator system is designed to operate with one car only in service, with two cars only in service or with a greater number of cars in service, I have provided a plurality of switching devices which may be manipulated to cause the cars to operate as a single-car or as a two-car or as a raulti-car system, when any one of these systems is desired. These switches are arranged to change the method of dispatching the cars in accordance with the type of system desired at any given time. Switches and 26 are arranged to be operated when it is desir d to operate car C alone, while switches 25' and 26 are arranged to be operated when it is desired. to use the car C alone. Switches 27 and 2' are arranged to be operated when it is desired to operate cars C and C jointly, as a two-car system.

Iviy system will be best understood with reference to a series of operations; first, that 0 car C operating as a single c'ar; second, that of C and C operating as a two-car system; and third, that of cars C, C and others (not illustrated) as a multi-car system.

-ssuming that elevator car C is to be operated as a single-car system, it will be presumed that switch 25 is open, while switch 28 is closed. The dispatcher may be stopped, there no point in dispatching a single car except when a call for service is desired.

Assuming that car C is at the floor selector arm A will have operated. switch 16, while switch 22 will be in close position. The closed condition or switch 22 wil cause up-direction-determining relay U to be energized by way of a circuit which extends from line conductor Ll, through conductors 3-0 and 31, contact ineinbe s b on a basement call relay BC, conductor 32, the normally-closed contact H164 here i switch 22 on floor selector FS, conductor 33, the coil of up-direction-determining relay UD, conductor 3 1, normally-closed contact members a on. down-directiondetermining relay conductors and 36, switch 26 and conductor 37, to line condr tor L2.

U p-directionete mining relay UD, when energized, completes a self-holding circuit which extends from. l ne conductor L1 to the coil of relay U23, as ously described, and thence, by way of conductor contact m mbers a on relay DD, conductors 35 and 38, contact members i) on relay U1) and conductors 39 and to line conductor L2. The car will. be in a condition to start upwardly in response to the operation of any of the call-buttons F21], F21), etc. or buttons C2, C3, etc.

Assuming that a person at the 2nd floor, desiring to travel upwardly, operates button Since the car C was stopped, a circ* it for energiw ing a dispatching relay DH is completed. This circuit extends from line conductor L1, through conductor 41, the normally closed contact membore a of each of the push-buttons F4, F31]. F3. FZU, FZD, FlU, Fll) and F3 in series relation with conductor 42, normally-closed contact membore a on up-direction switch 1 for car C, conductor 4:3, normally-closed contact members a down-direction switch 2 for car C, conductor 4 normally-closed contact members a on up-direc tion switch 1 for car 0', conductor l5, normallyclosed contact members a on down-direction switch 2' for car C, conductor 46 and thence, in series relation, through normally-closed contact members on both the up and down-direction switches for each of the cars in the bank of elevators to which my system will be applied, thence, by way of conductor 16, the coil of dispatching relay DR and conductors i? and 4.8, to line conductor L2. Hence, the operation of button F21) will open contact members a on this button and will open the circuit just described for dispatching relay Relay DR, being deenergized, will close its contact members d to complete a circuit for rip-direction switch 1 car C. This circuit extends from line conductor L1 tircugh conductors 30 and 4.9, whence it extends series relation through suitable door interlocking switches 50, 51, 52, 53 and 5% associated, respectively, with each of the doors D4, D3, D2, D1 and DB in the hatchway for car C, thence, by way of conductor 5", gate switch 56, conductors 5'! and 58, the coil of Lip-direction switch 1, conductor 59, contact members c on up-direction-detern1ining relay UD (now closed), conductors and 61, normallyclosed contact members b of transfer relay 8, conductors 62 and 63, contact members at on dispatching relay DR and conductor 48, to line conductor L2.

Updirection switch 1, vhen energized, supplies current to the field winding 6-1 of generator G to start the car upward y by way of contact members c on rip-direction switch 1, while contact members d on rip-direction switch 1 will complete self-holding circuit for this switch which extends from line conductor L1, to the coil of tip-direction switch 1, as previously described, and th nce, by way of conductors 59 and 64, contact members 01 on 1113-dl1'80tl011 switch 1, conductors 65 and 66, contact members b of floor-call stopping relay 9, conductor 67, contact members I) of car-call stopping relay 10 and conductor 68, to line conductor L2.

The car starts upwardly and, as the voltage output or" the generator G reaches a predetermined value, transfer relay 8 will be energized to open the initial energizing circuit for up-direction switch 1, leaving this switch energized by way of its holding c rcuit, thus placing the operation of the car now under control of floor-call stopping relay 9 or car-call stopping relay 10. The circuit for transfer relay 8 extends from loop circuit conductor 69, by way of conductor '70, the coil of transfer 8, and conductor '71, to the opposite loop-circuit conductor '12.

The car will continue upwardly until it approaches the 2nd floor, at which time, the fioorselector arm A wil have moved into a position just below tie dotted line indicated by the legend, 2nd, on floor selector FS, thereby bringing contact brush is on the arm A into engagement with segment 73 in the group of contact segments FCU. At this time, a circuit will be completed for energizing floor-call stopping relay which extends from line conductor Ll, through conductor 34, contact members 2) floor button FZU, conductors 75 and '16, contact segment 73, contact brush 19 on floor selector FS, conductor '77, the coil of car-call stopping relay 9, conductors '78 and 1'9, bypass button P on car C and conductors normally closed contact members 81 on load switch LS and conductor 82, to line conductor L2.

It will be observed, by an inspection of the floorcall buttons FE, F11), F11), etc., that each of these buttons is provided with a suitable magnet normally energized, except when a car arrives level with the corresponding floor, for the purpose of maintaining these push-buttons in actuated posi tion when operated. lhe magnet FZU' for button FZU connected in a circuit which extends from lin conductor L1, through conductor 83, the magnet coil F? conductor 84, normally-closed switch 85, constituting one of the group of switches RU on floor selector FS, conductor 36, normally-closed contact switch 85, constituting part of e group of switches RU on floor selector conductor 87 and thence, in series reration, through each of the corresponding switches constituting portions of the EU group of switches on each. or" the selectors for each of the additional elevators in the bank and thence, by way of conductor 83, to line conductor L2.

' when energized, -einbers b to break the holdwill bro at to a stop at the 2nd floor level by means of a brake or any suitable landing or levellin commonly used to stop elevators, which apparatus it is not de med necessary to more elaborately illustrate or describe.

As the car stops at 2nd iioor, the floor selector arm A will have moved into ali nment with. the dotted line on floor selector FS indicated by the le end, 2nd, and the switch-opera g device 20 will have moved between, and separated the contact members of, switch 35, thereby opening circuit for the holding magnet FZU for button FZU, resetting or restoring button to its normal unoperated condition.

It will be observed that transfer relay 8, which will be deenergized when tr e car is brought to a stop, is provided with a dashpot or other retarding device 89, preventing this relay from closing its contact members for a predetermined time after the car is brought to a halt. The time delay provided thereby allows sufiicient time for prospective passenger at the 2nd floor to open the door D2 at that floor, and the car gate before relay 8 will complete the circuit for restarting the car. It will be observed that the cannot restart with the doors and gates open since the circuit for the direction switches extends through the door ate switches, hence, passenger now on the car must reclose both the door D2 and the gate GS.

The passenger may then operate one of the car buttons C1, etc., dependent upon the floor to which he do Fee to travel. Assuming that the passenger desir s to travel to the Src floor and operates button C3, the car will be started up wardly to talre him to the 3rd door.

It will be observed that the fact that the car started upwardly to answer the 2nd floor call, has, by such initial moveinen..-, energized through-trip relay 6. The initial closing of the lip-direction switch completes a circ it for energizing through-trip relay 6 which extends from. line conductor L1, through conductors 30, 90 and 91, contact inernbers e on rip-direction switch 1, conductors 92 and 93, the coil of through-tri relay 6, 94 and 95, contact members on up-direction-determining relay U13 and con-- doctors 96 and so, to line conductor L2. Through-trip relay 6, when energi completes a self-holding circuit for itself which extends from line conductor L1, through conductors 97 and 98 and 99, contact members a through-- trip relay to the coil of through-tri and by way of conductor 94, to ductor L2, as previously traced for this Hence, independent of whether to on the car operates a button CB, C1,

car will again start upwardly as soon as the doors and gates are closed, since through-trip relay 6 opens the circuit for restarting relay 7, permit-- ting this relay to maintain its contact members closed until the car has reached tl e upper terminal. It will be observed that, with restart relay 7 deenergized, thus closing its contact mentbers, the circuit for energizing the "up-direction switch extends from line conductor Ll. through the door contacts by way of conductors 57 and 58 (previously traced for L'iD-dllECl-lOll switch 1) and thence to the coil of tip-direction switch 1 and thence, as previously traced, by way of conductors 59 and 63 whence, instead of extending to relay DR, the circuit now extends, through conductor 1G0, contact members of restart relay 7 and conductor 101, to line conductor L2.

However, it is assumes that the passenger boarding the the 2nd floor, desires to leave the car at the 3rd floor and, therefore, onerates button C3 to close contact members '0 on this button, which will be maintained closed by means of holding magnet 1&2 similar, in all respects, to holding magnets for the floor buttons previously described.

As the car approaches the 3rd floor, movable A. on floor selector FS will move contact b1" sh 18 into engagement with contact segment 1G3 (constituting one of the group of se ments CCU) and a circuit will be completed folperating car-call stopping relay 10, which extends from line conductor L1, through conductors 97, 98 and 104-, co tact ineinbers b of button con-- clo,

ductor 1%, contact segment 103, contact brush 18 on floor selector FS, conductor 1%, the coil of c -call stopping relay 1% and conductor 68, to line conductor L2.

Canoe-ll stopping relay, when energized, opens the holding circuit for the tip-direction switch 1 in he same manner did the operation of floor-call stopping relay 9, and the will be brought to rest at the 3rd floor.

However, it will be apparent trip relay remaining energized, w car to restart and move to the 4th floor, thus completing an up trip for this car.

It will be apparent that if, during tervening between the starti g of car (3 1st floor to the time it arrives at the other calls had been registered by actu b1 c" either up floor buttons F211 or FSU. th se b ttons would have supplied current i 1 ductor L1 to the respective contact segments group FCU to thereby cause energization of hall-call stopping relay 9 to cause the car to stop at the respective floors as it ap o ches "1.

While I have shown but four iloo my ilustrated system, it will be apparent that my tern may be adapted for as many floors as is desired by supplying additional segments and normally-closed switches upon the floor selector FS.

When the car a'rives at the u or top terminal. switch-operat floor-selector arm A will open s breaking the circuit which has, maintained upin actuated condition. thus pen to close its contact members a gize down-direction-determining rcla will al o be appat. that, when the car started from the 1st floor, throw-over switch 16 on door selector FS will have been moved to closed posi- 21 on .Ch. thereby up to this rig relay UIO oittin this relay t'i'on, hence, a circuit may now be traced for down-direction-determining relay DD, which circuit extends from line conductor L1, through conductors and 107, throw-over switch 16, conductor 108, the coil of down-direction-determining relay DD, conductor 109, contact members a on up-direction-determining relay UD (now closed), conductors 110, 111 and 112, switch 26 and conductor 37, to line conductor The operation. of relay DD prepares the car to travel downwardly in answer to calls for service in the down direction.

During the interval of changing from the updirection control to the down-direction control by the transfer of control from relays UD and DD, there will be a period during which the circuit for through-trip relay 6 will be open at contact members 6 on relay UD and also during this period, the holding coils for the car-buttons CB, C1, etc. will be opened by contact members e on relay UD. It will be observed that, with up-direcnon-determining relay UD or down-directiondetermining relay DD closed, a circuit from line conductor L1, through conductors 97 and 98, will be completed for the holding coils for buttons CB, Cl, etc. in series relation, which extends thence by way of conductor 113 and either by way of conductor 95 and contact members e on up-dimotion-determining relay UD, or by way of conductor 114 and contact members e on downdirection-determining relay DD.

With no calls for service, (that is, no floorcall buttons F4, F311, etc. in operated condition) and the car stopped at the top floor, relay DR will have its coil energized to prevent restarting of the car, and, with no buttons CB, G1, etc. 0perated, restarting relay 7 will have its coil energized to prevent restarting of the car and hence, the car will remain at the uppermost floor until a button at another floor or a button in the is actuated. The operation or a button at one of the floors causes the car to start in the down direction in the same manner as was described for the original starting of the car. However, assuming that someone at the 4th flOOI boards the car and operates one of the push-buttons CB, C1, etc, the opening of contact members a on any of the car-ca1l buttons C13, G1, etc. will cause deenergization of restarting relay 7 by opening the normal circuit for this relay, which extends from line conductor L1, through conductors 97 and 115, contact members a on each or the car buttons in series relation, conductor 116, the coil of restarting relay 7, conductor 117, contact members b on through-trip relay 6 (now deenergized as previously explained), and conductor 161, to line conductor L2.

However, as soon relay 7 is deenergized to close its contact members, a circuit will be completed for the down-direction switch 2 which extends from line conductor L1, through conductors 30 and 19, door switches 50, 51, 52, 53 and 54, conductor 55, gate switch 56, conductors 57 and 116-, the coil of down-direction switch 2, conduetor 11.9, contact members 0 on down-directiondetermining relay DD, and conductors 120 and 61, contact members I) of transfer relay 8, conductors 62, 63 and 160, the contact members of restarting relay 7 and conductor 101, to line conductor L2.

The car will start downwardly, stopping in response to any actuated call-button or car-button, in the manner described with reference to stops the up direction except that the floor selector arm A will now be in a position to engage contact brushes 12 and 13 with segment groups CCD and FCD, respectively, since the car is travelling downwardly.

The transposition of the floor-selector arm A from engagement with its up groups of segments to engagement with its down groups of segments, occurs when the up-direction-determining relay UD drops out and the down-direction-determining relay is picked up. It will be observed that the circuit for magnet D8, which causes the selector arm A to rock to what may be termed the down position, extends from line conductor L1, through conductors 30, 121 and 122 contact members (I on down-direction-determining relay DD, conductor 123, the coil of down selector magnet DS, conductors 124, 125 and 79, bypass switch P, conductor 80, contact members 81 on load switch LS, and conductor 82 to line conductor L2. Hence, until relay DD drops out when the car arrives at the lowermost terminal, selector arm A will be in such position that it can engage only the down segments CCD, FCD and switches RD.

Since the car, once started downwardly, will continue to travel downwardly by virtue of energization of through-trip relay 6, restarting after each stop, it is desirable, in some instances, that the car should be stopped prior to the time of reaching the basement. In other words, it may be desirable that the first floor should be the normal terminal for this car. Hence, I have located switch 16, which normally reverses the direction-determining relays U13 and DD at the end of a down trip, to be actuated when the car arrives at the 1st floor rather than at the basement floor. But it will be observed that the segment 126 in group FCD on the fioor selector will be continuously supplied with current from line conductor L2 through contact members 17 on basement button FB so as to cause energization 115 of floor-call stopping relay 9 each time the car approaches the 1st floor. Hence, the car will stop at the 1st floor on each down trip unless a call exists for service at the basement floor.

Assuming that no call exists at the basement 120 floor, the car will be stopped, since a circuit extending from line conductor L1, by way of conductors 127 and 128, normally-closed contact members b on floor button FB at the basement iioor, conductors 129, 130 and 131, segment 126, brush 13, conductors 132 and 77, the coil of floorcall stopping relay 9, conductors 78 and 79 bypass button P and conductor 80, contact members 81 on load switch LS, and conductor 82, to line conductor L2 will be completed to operate car-stopping relay 9. I

As the car arrives at the 1st floor, switch 16 will be opened to thereby drop out down-direction determining relay DD and to permit lip-direction-determining relay UD to be energized to prepare the car for another upward trip.

Assuming, however, that someone at the basement, desiring to use the car, operates button FB, the circuit for supplying current to segment 126 will be broken at contact members I) on button F5 while a circuit will be completed to segment 133 to stop the car at the basement floor and, also, a branch of that circuit will be completed through coil 13 1 on basement call relay BC. This circuit extends from line conductor L1, through conductor 135, contact members 0 on basement call relay PB and conductor 136, to junction point 137, one branch of the circuit extending by way of conductor 138, to segment 133, while another branch of the circuit extends, by way of concluctors 139 and 140, to the coil 134 of basement call relay BC and by conductors 141 and 48, to line conductor L2.

Basement call relay BC, when energized, prevents closing of the circuit for up-directiondetermining relay UD by opening its contact members b, while the closing of its contact members a shunts switch 16 by way of conductors 31 and 142 to prevent opening or dropping out of down-direction-determining relay DD as the car approaches or passes the 1st floor. Hence, the car will continue downwardly to the basement floor, stopping thereat in the same manner as described for other stops.

When the car arrives at the basement floor, switch-operating device 14 on selector arm A will engage and open switch 143 to restore the floorbutton F3 to normal condition, thereby deenergizing basement call relay BC, permitting this relay to open the shunt around switch 16 (now in open-circuit position) and permitting the closing of the circuit for up-direction-determining relay UD to prepare the car for an upward trip. In like manner, the actuation of car-button CB will cause the car to move to the basement floor, since operation of this button energizes a second coil 144 on basement call relay BC, in the same manner as previously described for the operation of coil 134 by floor-button FB.

It will, therefore, be apparent that the car will operate between the 1st and 1th floors at all times except when a call exists for service at the basement floor, at which time, the car will be prevented from reversing at the 1st floor but will be carried to the basement in answer to that cail.

It will be observed from the foregoing description that the car C may be operated as a single car which will operate in response to calls for service, collecting all of the passengers who desire to travel in the up direction during the upward trip and collecting all of the passengers desiring to travel downwardly during the downward trip.

A further condition of operation will be satisfied by my system, namely, that of having the car standing at the lower terminal or 1st floor when a call for service is registered at the base ment floor. The operation of the basement button FB or CB operating relay BC will cause the car to respond to that call.

It will be observed that, when the car is standing at the 1st floor, switch 16 having been opened, relay UD will be closed to prepare the car for an upward trip, while the floor-selector arm A will have been shifted to the up position, so that the call for service at the basement floor must reverse these connections in order that the car may start downwardly. By extending the circuit for the up-direction relay UD through contact members I) on relay BC and by shunting switch 16 by contact members a on relay BC, the previously set condition of the direction-determining relays will be reversed, and the car may start downwardly to respond to the call,

It will be observed that car C may be operated alone as a single car system by closing switch 26 and opening switch 25, whereupon car C will operate in precisely the manner previously d scribed for car C.

Assuming that it is desired to operate two cars as a two-car system, switches 26 and 26 will be opened, switches 25 and 25 will be opened and switches 2'7 and 27 will be closed.

In this event, one of the cars will be parked or have its normal station at one of the terminals, while the other car will have its normal station at the opposite terminal, and, as one car moves upwardly, the other car will be automatically started downwardly to reverse the positions of the car.

Assuming that car C is at the lowermost terminal and car C at the uppermost terminal, car C will have its up-direction-determining relay UD energized, while car C will have its down-direction-determining relay DD energized. Assuming that car C was the first car to reach its terminal opened switch 16, relay DD will be deenergized to prepare a circuit for actuating relay UD in the manner described with reference to the one-car operation. However, the circuit for U3) cannot be completed until car C arrives at its upper terminal, since now the energizing circuit for relay UD extends through normally-closed contact members 7 on up-directiondetermining relay UD for car C.

This circuit extends from line conductor L1, through conductors 30 and 31, contact members b on basement call relay BC, conductor 32, switch 22 on 11001 selector FS, conductor 33, the coil of updirection-determining relay UD, conductor 34, contact members a on down-direction-deterj mining relay DD, conductors 35 and 36, switch 27, conductor 151, contact members 1 on updirection-determining relay UD and conductors 152 and 40, to line conductor L2. Hence, the

up-direction-determining relay for car C cannot be energized until car C arrives at its upper terminal and drops out its up-directiomdetermining relay. However, as soon as the car C arrives at its upper terminal, up-directiondetermining relay UD will be energized.

At the same time, down-direction-determining relay DD for car C, having been deenergized, will complete a circuit for energizing direction-determining relay DD for car C by way of a circuit which extends from line conductor L1, through. conductors 153 and 154, switch 16 on floor selector FS, conduct-or 155, the coil of down-direction-determining relay DD, conductor 156, contact members a on up-direction-determining relay UD, conductor 157, switch 27, conductor 158, normally-closed contact members i on downdirection-determining relay DD for car C and conductors 159 and 40, to line conductor L2. Both cars are now in condition to start tripscar C to start an up trip and car C to start a down trip.

However, neither car may start until a call is registered, by virtue of the fact that both cars are under the control of dispatching relay DR, the coil of which will be energized since all of he floor buttons FB to F4 have their contact members a closed and both cars will have their direction switches l and 2, and 1 and 2, deenergized, also, no car-buttons in either car having been operated, relay 7 for car C and relay 7 for car C will be energized, thus preventing starting of the car through the contact members of these relays.

Assuming now that a person at the 2nd floor, desiring to travel upwardly, operates the button F211, the cars will be started. Car C will be started because relay DR will be deenergized, which operation has been previously described with reference to the single-car operation. Car

C will also be started, since the circuit for its direction switches will be closed through contact members a on dispatching relay DR, which circuit extends from line conductor L1, through conductors 153 and 160, door switches associated with doors D4, D3, D2, D1 and DB associated with car C, conductor I61, gate switch GS, conductors 162 and 163, the coil of down-direction switch 2, conductor 164, contact members 0 on dovw1-direction-determining relay DD, concluctor 16-5, contact members b of transfer relay 8, conductors 156 and 167, contact members 0'. on dispatching relay DR and conductors 47 and 48, to line conductor L2. Through-trip relay 6 for car C will be energized as described for the single-car operation, while through-trip relay 6 for car will also be energized by way oi a similar circuit, hence, car C will be started upwardly and car C will be started downwardly.

Car C will stop at the 2nd floor to take on the passenger, in the manner previously olescribed with reference to a single-car operation, while car C will continue downwardly, answering all down calls for service until it reaches the 1st floor, whereupon it will open switch 16 to drop out direction-determining relay DD and will thereafter wait at the lower terminal until car C has arrived at the upper terminal, since updirection-determining relay '09 cannot be energized to prepare ear C for upward trip until updirection-determining relay UD for car 8 has been deenergized upon the arrival of that car at its upper terminal.

The purpose of so interlocking the directiondeterniining relays for cars C and C is that, it one car should arrive at its terminal before other car has answered all the calls in the di- "ection in which it is travelling, the car reaching the terminal would immediately reverse and, as soon as it started, would open the contact 1ne1nbers a on its direction switch to deenergize relay DR, having the eiiect of indicating that a call for service existed even after the opposite car had answered all the then existing calls. In other words, the cars would be forced to continuously travel upwardly and downwardly u perhaps by accident, one reached its terminal at just the same time that the other car reached its terminal, before either of the cars would stop, even though no calls had existed for service dur ing several trips. However, by such interlocking as that previously described, one car is forced to wait at its terminal until the opposite car has arrived at its terminal, and then, if no calls for service exist, these cars will remain stationary until another call is registered, whereupon both cars will again start, as previously each to make a through trip to answe such calls. will be apparent that the floor-bar? ll Y Kelli/"v button FE or the car-basement-call b and CB will be effective to cause the cars to move to the basement whenever such service is de ed, since the circuit for basement call relay BC has a parallel branch extending from conductor 129, by way of conductor 158, to the coil 169 of a bascrnent call relay BC and thence, by way of ccnductor li e, to line conductor L2, so that this relay will operate to apply the basement call to car 0 as well as to car C. In on, base rnent call relay '50 has an additional coil lZl circuit with car-hutton CB so this car may be sent to the basement to permit passengers on car C to leave the car at the basement floor. By providing relays ,C and BC, each an additional operating coil connected, 1 p 3-- tively, to the car-buttons, individual the associated cars, that car upon which a assenger, wishing to go to he basement, is 1 g may, alone, be sent to the without necessitating tr e operation of the other car to the base with men; but permitting this car to continue its norrnal operation.

it till, therefore, be apparent that my systei. may be zed with two only, operating a two-cal sy tem in wl h one car will move cowardly, wh the other is moving downwar y, e 1- giving service wherever Mich service is lij d.

sir-d to use my sys elevator 6' will be opened, be closed and the indicated by the legend Dispatcherfi Will. started to time the departure of several cars iron terminal r from their 1 te inal, i switch being provided is" this purpose.

have i lustrated the dispatcher as comprisco t segments 23 and 23, 24 and 24, for dispatch g "-vo cars though is to be understood a ton it l val between 'll shortened.

l a all f the cars are at the 1st ction-deter "ning relays DD, and those wit.. Ldditional cars will ced, since each or" the cars will have 16 or 16, on associated n open-circuit condition. Hence, i sing up direction- U2) and others associ- Lilowever, these circuits the connection beese relays and line at he dispatching seg- 1s rotated to bring its ng relays additional ca ring that se on to cn e 1t is brought into a contact member 180, a ed for the updirection-de- Qor car C which extends line conductor th ough conductors S5 and 31, contact members 0 on basement call relay BC, conductor 32, switch 22 on floor selector FS, conductor E, coil of up-direction-deter ring relay UD, conductor contact members a on d wn-direction-deterr ng relay DD, conductors iSl, contact members and 23 of the di patcher and conductors 182 and 32, to line col du tor Up-direction-deterrni relay (ID will, therefore, be en to prepare the car C to travel upwardly. In this however, switch 25 is in closed-circuit positio and hence, it is not necessary that a call shall e t in order to get the car C to start but this car will be automaticaly 5 ed by the d atelier to start upwardly to l alce a coinpi upward trip. The closing of this car to stop in response The car C, when started, continues to travel with reference to both th single-car operation to GLJB two-car operation, since through-true relay 6 will nave been energized as previously described.

When car C arrives at the upper terr it will open its contact switch 22 to drop out the updirection-deterrnining relay UD, but the downdirection-determining relay DD will not lYIlIHBjr ately pick up, since the only way in which the circuit for this relay may iow be completed is through dispatcher segment 24. When dispatcher segment 24 is moved into engagement wit its cooperating brush, downdirection-determi' ing relay DD will be energized and, since swit h is close placing a permanent call upon car C, the car will immediately start downwardly to complete down trip. When the car C arrives at the lower downdirection-deterrnining relay DD drops out upon the openin switch 16 on floor selector FS, the car eta lower terminal floor until the dispatcher 23 again engages brush 180 to start this its next up trip.

In like manner, dispatcher se; will cause the starting oi car C- tion and in the down direction, respec these segments are brought into engagement with their cooperating brushes.

It will be observed that floor-call buttons FB, FlD, Fill, etc. have their circuits e: tending to the FCU and FCD groups of ssgr ents on floor selector paralleled to corresponding segments in groups FC and FCD on ca" C, that the calls registered on the floor-call ions will be common to all cars l the bank, whereas, the carcall buttons CB, G1, etc. on car and buttons CB, 01', etc. on car C -.re in the .-dl.llllj con to the CCU and CCD groups of segn on t" t selector associated with the oective car hence, calls set up by the call buttons will be answered only by the associated to rotate about its pivot LS? open contact members 81, breaking the circuit for floor-call stopping relay in the same manner tho bypass switch P l l operated, if car is loaded, there will be no point in iitcalls for service from the various floors. Load switch vii in addition, close its contact 1: embers place a shunt around the disp "her see; i to automatically dispatch this car without waiting for the dispatch impulse to be given by the clispatcher. The car will th 1 travel upwardly, stopping in answer to calls registered on car butt as 01, C2, etc., but will not stop in answer to floorcall buttons F1, F2, etc., until the load on car '3 is reduced by passengers leaving the car, percontact its mitting load switch LS to reclose members 81.

Each of the other cars in the bani; manner, be provided with a loa form a similar service for those cars.

In the manner described wit -:l8l'lC to single-car operation and the two-car o ation, all of the cars in the bani; will ope normally to the ist floor a lower tcrnnnal, but each of the cars is adapted to t basement floor whenever a basement call e1. each the cars is or BC to perforn those describe The featurlower terminal permit, basement when ser cc is desirei. essary that a departure s usual method of operating e fl or lanteri indicate the direc" l the car is to 'ravel whenever it rnal: s a stop any of the floors.

I have indicated a pluralit oi floor lanterns,

one set for each of the co t 0 bank, ccinprising an up lantern a a down lantern at each of the doors the cars cept the upper termi al fie: lb iloor rn only which ar prodded w approach of a to the terminal lanterns LlU, are connected, respectively, t U ments on floor selector L ting a group of segments designated by reference charecter LU, to be engaged successively by a contact brush 186 carried by movable as the car C approaches the corresponding floor.

In like manner, down-floor lanterns L13, L21), and L33 are connected to indi idual segments on floor selector FS constituting a group of segments designated by the reference character LE), to be engaged by a contact brush as the car approaches the corresponding floors when travelling in the down direction.

' Car-call stopping relay 1% and floor-oall stopping relay 9 are each provided with. norm" 185 and t c brushes whenever either of relays is energized to cause the car to stop any floor.

If the car is to stop in response to a floor call at the 2nd floor, when travelling upwardly, lantern LZU will be lighted as soon as floor-call stopping relay 9 is energized to cause the to stop at that floor. The circuit :ior lantern tends from line conductor L1, h conductors 97, 98, 138 and 139, contact nee ibers a of floor call topping 9, conductors 198 and 191, brush 1S6, segment 192 grou LU, conductor 193, lantern L2U, conductor 19;, by switch P, conductor 80, contact member 81 on load switch LS and conductor 82, to line conductor L2.

When the car is brought to a stop at the 2nd floor, and relay 9 is deenergized (since in h 19 will have moved off segment 73 in group lo as previously described for the 2nd floor stop),

the lantern will be extinguished unless prevention means are provided. In order to prevent extinguishing the lantern L2U until the car leaves the 2nd floor, I have provided normally-closed contact members a on transfer relay 8, which are arranged, in any suitable manner, to be closed quickly upon the reduction of voltage output or" the generator G when the car is brought to a stop. In other words, contact members a are not affected by the time delay occasioned by dashpot 89. When contact members a on relay 8 are closed, a shunt circuit around contact members a on floor-call stopping relay 9 is completed to maintain current in the circuit for lantern L2D during the entire time the car remains at the 2nd floor.

It will be observed, from an inspection of the floor selector FS, that segment 192 in group LU extends slightly beyond the dotted line representing the position of the car at the 2nd floor level, hence, during the entire time the car is at the 2nd floor, brush 186 will be in a position to complete the circuit for L2U through segment 192.

The down lanterns are operated in a similar manner by engagement of brush 187 with the contact segments constituting group LD. Also, the energization of car-call stopping relay 10 will energize the floor lantern corresponding to the direction of travel of the car and to the fioor approached by the car, since contact members a on relay 10 are also arranged in the circuit for brushes 186 and 187 in the same manner as are contact members a on floor-call stopping relay 9. 7

However, when the car C approaches the 1st floor with no call existent to carry it to the base ment floor, it is desirable that lantern LlU shall be lighted to indicate that the car is ready to proceed, on an upward trip when it leaves the 1st floor instead of lighting lantern LlD to give a false indication that the car is to travel downwardly from that floor. For this reason, I have indicated that the conductor for connecting segments 196 to lantern LlD passes through normally-open contact members c on basement call relay BC, hence, unless basement call relay BC is energized to carry the car to the basement, floor lantern LlD will not be lighted, even though the car stops at the 1st floor on its way down.

In addition, I have illustrated a branch circuit for energizing lantern LlU when the car approaches the 1st floor in the down direction if no call exists for service at the basement floor. This circuit extends from conductor 197 (connecting segment 198 on the up side of the floor selector PS to the lantern LlU), by way of conductor 199, normally-closed contact members d on basement call relay BC and conductors 209 and 201, to segment 196 on the down side of the floor selector FS. It will be remembered that segment 196 is the segment normally used for lighting lantern LlD, hence, when brush 187 engages segment 196, lantern LlU will be lighted instead of lantern LlD, unless basement call relay-BC is energized, at which time, the connections will be reversed to light lantern LlD instead of lantern LlU. In this manner, I avoid the confusion resulting from a false indication being given by the floor lantern associated with car C.

In like mannenthe lanterns LD, LlD, LlU, L2D, L2U', L3D, L3U' and L4 will be actuated by the, approach of car C to the corresponding floors if a stop is to be made by car C at those floors.

It will be understood from the foregoing disclosure that I have provided an elevator system which may include as many cars in a bank as is desirable, and which, through the simple manipulation of switches at a dispatching station, may be converted from a multi-car system in which the cars will operate in all respects identical with that of a bank of cars controlled by an individual attendant on each car; which may be operated as a two-car bank with the remainder of the cars out of service when traflic conditions warrant; or which may be operated as a single-car system with the remainder of the cars out of service, without the necessity, in any case, of having an attendant on any car.

It will be understood that the embodiment of my system shown and described is illustrative only, and that I do not desire to be limited to any of the details shown herein, except as defined in the appended claims.

I claim as my invention:

1. In a control system for a plurality of elevator cars operable past a plurality of floors between two terminals, means individual to each of said cars for starting said car in either direction, call means for said floors operable to stop any of said cars at corresponding floors, means operable by the initial starting of said car in either direction for biasing said car to continue to travel after each stop in the corresponding direction to the corresponding terminal, and means selectively operable to cause consecutive actuation of the car starting means for all of said cars at regular intervals of time, to cause actuation of the starting means for one car by the initial starting of another car or to cause the starting means for one car only to be actuated upon actuation of any of said call means.

2. In a control system for two elevator cars operable past a plurality of floors between two terminals, call means for said floors for calling said cars and for stopping them upon arrival at the corresponding floors, starting means for each of said two cars, both operable upon actuation of any of said call means, means operable upon starting of either car to cause said car to move to the terminal in the direction in which it starts and means for preventing the starting of either car from a terminal until the other car arrives at the other terminal.

3. In a control system for a plurality of ele vator cars operable past a plurality of floors, call means at each floor for calling said cars to said floor and for stopping the first of said cars to arrive at said floors, means operable upon starting of one car for starting the other of said cars and means for preventing the starting of either of said cars from a terminal floor until both are at terminal floors.

4. In a control system for an elevator car operable past a plurality of floors between two terminals, call means for said floors for calling said car to said floors and for stopping said car upon arrival at the corresponding floor, starting means for said car, means operable upon actuation of any of said calling means for actuating said starting. means and means, operable in response to the presence of a predetermined load in said car, for actuating said starting means independent of any of said call means.

5. In a control system for an elevator car operable past a plurality of floors between two terminals, call means for said floors for calling said car to said floors and for stopping said car upon arrival at the corresponding floor, starting means for said car, means, operable by actuation of any of said call means, for operating said start ing means, timed means for operating said starting means, and change-over mechanism operable to determine which of said last two mentioned means is to control said starting means.

6. In a control system for an elevator car operable past a plurality of floors, means for each of said floors for registering calls for service at the corresponding floors, means for normally limiting the extent of travel of said car to a zone between certain of said floors independent of the actuation of the corresponding call means and means responsive to the actuation of a call means for a floor outside said zone for rendering said limiting means ineilective.

7. In a control system for a plurality of elevator cars, means for operating each of said cars including startin mechanism, and switching mechanism responsive to the position of one or said cars for controlling the starting mechanism for the other of said cars.

8. In a control system for a plurality of elevator cars operable between two terminal landings, means to control the starting of one of said cars from a terminal landing comprising starting connections for that car, and means comprising switching means responsive to the approach of the other of said cars to the other terminal landing for controlling said starting connections.

9. In a control system for a plurality of elevator cars operable between upper and lower terminal positions, starting mechanism for each of said cars, and means adapted to prevent actuation of the starting mechanism for either of said cars to cause that car to leave a terminal position until after the arrival of the other of said cars at the other terminal position.

10. In a control system for a plurality of elevator cars, starting means for each of said cars, and means adapted to respond to the actuation of the starting means for either car for causing actuation of the starting means for the other car.

11. In a control system for a plurality of elevator cars operable between two terminal landings, starting means for each or" said cars, and means adapted to respond to the actuation of the starting means for either car to cause that car to leave one terminal landing, and, in the event said cars are standing at opposite terminals, to cause actuation of the starting means for the other car to cause that car to leave said other terminal landing.

12. In a control system for a plurality of elevators cars operable past a plurality of floors, up and down starting means for each of said cars, call-registering means for each of said floors, and means adapted to respond to operation of any one or" said call-registering means to cause actuation of the Lip-starting means for one of said cars and of the down starting means for another of said cars.

13. In a control system for a plurality of elevator cars operable in hatchways past a plurality of landings intermediate upper and lower terminal positions, up and down mechanism for each of said cars, call-registering means associated with each of said landings, and means adapted to respond to operation of any of said call-registering means, if said cars are standing at opposite terminal positions, to cause actuation of the up-starting mechanism for one of said cars and to cause actuation of the down starting mechanism for the other of said cars.

i i. In a control system for a plurality of elevator cars operable past a plurality of floor landings between two terminals, up and down starting mechanism for each of said cars, up and down call-registering means for each of said landings, and means adapted to respond to operation of either call-registering means for any floor, in the event said cars are standing at opposite terminals, to cause actuation of the upstarting mechanism for one of said cars and to cause actuation of the down starting mechanism for the other of said cars.

15. In a control system for a plurality of elevator cars operable between a plurality of landings between two terminals, means to control the initial starting of either of said cars from a terminal position in accordance with the position or" the other of said cars, and means rendered effective upon initial starting of either car from a terminal position to cause that car to continue to the opposite terminal position.

16. In a control system for a plurality of elevator cars operable between a plurality of landings between two terminals, means to control the initial starting of either of said cars from a terminal position in accordance with the position of the other of said cars, means rendered eifective upon initial starting of either car from a terminal position to cause that car to continue to the opposite terminal position, and call-registering means associated with each of said floors operable to cause the stopping of either of said cars at the associated floor.

17. In a control system for a plurality of elevator cars operable past a plurality of floors between two terminal floors, means to control the starting of either of said cars from a terminal floor in accordance with the position of the other of said cars, and means to efiect the restarting of either of said cars from an intermediate floor regardless of the position of the other of said cars.

18. In a control system for a plurality of elevator cars operable past a plurality of floors between two terminal floors, means to control the starting of either of said cars from a terminal floor in accordance with the position of the other of said cars, means to effect the restarting of either of said cars from an intermediate floor regardless of the position of the other of said cars, and call-registering means for each intermediate fioor operable to cause the stopping of either of said cars at the associated floor.

19. In a control system for an elevator operable past a zone of adjacent floors and an additional floor beyond the lower limit of said zone, means associated with up-direction travel of said car, means associated with down direction travel of said car, transfer mechanism disposed to respond to the approach of said car to the floor corresponding to the lower limit of said zone to render said down-direction means ineffective and to render said up-direction means effective, and means to render said transfer mechanism inefiective, said last-named means comprising call-registering means associated with said additional floor.

20. In a control system for an elevator car operable past a zone of adjacent floors and an additional floor below the lower limit of said zone, control means for said car comprising updirection and down-direction mechanism, transfer means disposed to respond to the approach of said car to said lower limit of said zone to render said down-direction mechanism inefiective and to render said up-direction mechanism efiective, call-registering means associated with said additional floor, and means adapted to respond to operation of said call-registering means to render said up-direction mechanism inefiective and render said down-direction mechanism effective.

21. In a control system for a plurality of elevator cars operable past a plurality of floors, passenger-operated call means for moving said cars to, and stopping them at, said floors, and means, operably responsive to the operation of one of said call means to move one of said cars in one direction to a floor, for moving another of said cars in the opposite direction.

22. In a control system for a plurality of elevator cars operable past a plurality of floors between two terminal floors, passenger-operated call means for moving said cars to, and stopping them at, said floors, and means, operably responsive to the operation of one of said call means to move one of said cars, for causing said cars to move to, andto park at, opposite terminals.

23. In a control system for a pair of elevator cars operable past a plurality of floors between two terminals, up-direction and down-direction means for registering calls to move said cars to, and to stop them at, said floors and means, operably responsive to the registration of a call in one direction for one car, for establishing a call in the opposite direction for the other car.

24. In a control system for an elevator car operable past a zone of adjacent floors and an additional floor beyond one limit of said zone, means associated with travel of said car through said zone in one direction, means associated with travel of said car through said zone in the reverse direction, circuits and contact members associated with said directional means, transfer means disposed to respond to the arrival of said car at said limit to open contact members in the circuit for one of said directional means and to close contact members in the circuit for the other of said directional means, and means comprising call-registering means associated with said additional floor for rendering said transfer means ineffective.

FRANK E. LEWIS. 

